Crystalline forms of phthalazinone compound

ABSTRACT

The present specification provides crystalline forms of 4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one hydrochloride, methods of preparing the same, and pharmaceutical compositions comprising the same.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Ser. No. 63/013,276 filed 21Apr. 2020, the content of which is incorporated herein by reference inits entirety.

TECHNICAL FIELD

The present invention relates to crystalline forms of a phthalazinonecompound of Formula 1, methods of preparing the same, and pharmaceuticalcompositions including the same. More particularly, the presentinvention relates to crystalline forms of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride, methods of preparing the same, and pharmaceuticalcompositions including the same.

BACKGROUND ART OF INVENTION

U.S. Pat. No. 9,682,973 (“US '973”) discloses4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-oneof Formula 2 and pharmaceutically acceptable salts thereof havinganti-cancer activity as poly(ADP-ribose) polymerase (hereinafterreferred to as “PARP”) inhibitors:

The compound of Formula 1, which is a hydrochloride of the compound ofFormula 2, is also disclosed in US '973.

US '973 discloses a method of preparing the hydrochloride compound ofFormula 1 from the compound of Formula 2. In particular, after thecompound of Formula 2 is dissolved in dichloromethane and then cooleddown to 0° C., a 1 N HCl aqueous solution is added thereto, stirred atroom temperature for 1 hour, and concentrated, to prepare the compoundof Formula 1.

However, when trying to conduct a scale-up process based on the methoddisclosed in US '973, the compound of Formula 1 was obtained in aviscous oil phase, not crystalline solid. Such an oil phase has lowpurity and stability compared to a crystalline solid, and is lessdesirable for commercial production. Further, since the method accordingto US '973 requires a concentration process, this method may not bepreferred for the commercial large-scale production of a medicinal drugsubstance.

Furthermore, the preparation method of US '973 uses dichloromethane as asolvent, which may remain as a residual impurity even after removal. Asa result, the preparation method of US '973 could potentially be lessdesirable in terms of safety due to strict maximum requirements of thesolvent.

DISCLOSURE Technical Problem

One aspect of the present invention is to provide a crystalline form of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride, which has improved stability and purity and which is moresuitable for mass (i.e., commercial or large-scale) production.

Another aspect is to provide a pharmaceutical composition containing thecrystalline form of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride.

Another aspect is to provide a method of preparing a crystalline form of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride.

Other objectives and advantages of the present invention will becomeapparent from the following detailed descriptions along with theappended claims. Certain content not described in the presentspecification may be sufficiently recognized and inferred by thoseskilled in the art or similar fields of the present invention, and thusdescription thereof is omitted.

Technical Solution

In one aspect of the present invention, there is provided crystallineform of a compound of Formula 1, characterized in exhibiting an X-raypowder diffraction (XRPD) pattern comprising peaks at 2θ±0.2° values of13.7°, 15.9°, and 24.1°:

In another aspect, there is provided a pharmaceutical compositioncomprising a crystalline form of the compound of Formula 1 as an activeingredient and at least one pharmaceutically acceptable carrier ordiluent.

In another aspect, there is provided a method of preparing a crystallineform of the compound of Formula 1, the method comprising:

dissolving4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onein one or more solvents selected from a group consisting of a C₁-C₃alcohol, acetone, ethyl acetate, and methyl t-butyl ether; and

adding a hydrochloric acid solution.

In accordance with the present invention, in an embodiment, the methoddoes not involve the use of a concentration process. As such, thepresent method would be more preferable for a commercial mass process.

In another aspect, there is provided a crystalline form of the compoundof Formula 1 prepared by the above-described method.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows an X-ray powder diffraction (XRPD) pattern of crystallineform A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride prepared in Example 1.

FIG. 2 is a graph illustrating the results of differential scanningcalorimetry (DSC) of crystalline form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride prepared in Example 1.

FIG. 3 is a graph illustrating the results of thermogravimetric analysis(TGA) of crystalline form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride prepared in Example 1.

FIG. 4 is a comparative graph illustrating XRPD patterns of crystallineform A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride prepared in Example 1 to Example 6.

FIG. 5 shows an XRPD pattern of crystalline form C of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride.

FIG. 6 is a graph illustrating the results of DSC of crystalline form Cof4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride.

FIG. 7 is a graph illustrating the results of TGA of crystalline form Cof4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride.

FIG. 8 shows an XRPD pattern of an amorphous form of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, the present invention will be described in greater detail.Unless otherwise defined, all technical terms used in the presentinvention have the same meaning as commonly understood by those skilledin the related art of the present invention.

The contents of all publications cited as reference documents herein areincorporated in the present specification by reference in theirentirety.

Descriptions and embodiments disclosed in one portion of the presentinvention may be applied to other descriptions and embodiments in otherportions of the present invention. That is, all combinations of variouselements disclosed in the present invention belong within the scope ofthe present invention. Additionally, the scope of the present inventionshould not be limited by the specific descriptions described hereinbelow.

In addition, although a preferred method or sample is described in thespecification, those similar or equivalent thereto fall within the scopeof the present invention. In addition, the term “comprising” is intendedto have an open-ended meaning and permits the inclusion of additionalelements that are not identified.

Unless otherwise indicated, all numbers expressing quantities ofingredients, properties such as molecular weight, reaction conditions,and so forth as used in the specification and claims are to beunderstood as being modified in all instances by the term “about.”Accordingly, unless otherwise indicated, the numerical properties setforth in the following specification and claims are approximations thatmay vary depending on the desired properties sought to be obtained inembodiments of the present invention. As used herein, the term “about”refers to being within 5% of a particular value or range, and morepreferably within 1% to 2%. For example, “about 10%” refers to 9.5% to10.5%, and preferably, 9.8% to 10.2%. For another example, “about 1000°C.” refers to 95° C. to 105° C., and preferably, 98° C. to 102° C.

Unless otherwise specified, it should be apparent to a skilled person inthe art that the values of peaks from X-ray powder diffraction studiesreported in this application are associated with experimental errorstypically observable in this field. Specifically, a peak is interpretedto be located within the angle variation ±0.5° of the value reportedherein. Preferably, a peak is interpreted to be located within the anglevariation ±0.2° of the value reported herein, more preferably, withinthe angle variation ±0.1°.

Crystalline Forms of Compound of Formula 1

One aspect of the present invention provides a crystalline form of thecompound of Formula 1 below, characterized in exhibiting an X-ray powderdiffraction (XRPD) pattern comprising peaks at diffraction angles2θ±0.2° values of 13.7°, 15.9°, and 24.1°.

Hereinafter, the crystalline form is referred to as Crystalline Form A.

In one aspect, Crystalline Form A may exhibit an XRPD pattern comprisingpeaks at three or more and, preferably four or more, 2θ±0.2° valuesselected from the group consisting of 9.1°, 11.9°, 13.2°, 13.7°, 15.9°,16.8°, 18.1°, 23.2°, 24.1°, 25.5°, and 26.6°.

In particular, Crystalline Form A may exhibit an XRPD pattern comprisingpeaks at 2θ±0.2° values of 9.1°, 13.2°, 13.7°, 15.9°, 16.8°, 24.1°, and26.6°.

In more particularity, Crystalline Form A may exhibit an XRPD patterncomprising peaks at 2θ±0.2° values of 9.1°, 11.9°, 13.2°, 13.7°, 15.9°,16.8°, 18.1°, 23.2°, 24.1°, 25.5°, and 26.6°.

The XRPD pattern may be obtained when irradiated with a Cu-Kα lightsource, for example, using a D8 Advance (Bruker ASX, Germany) analyzer.The Cu-Kα light source may have the wavelength of 1.54056 Å.

These peaks may be those having a relative intensity (I/I_(o)) of about10%, more specifically, about 15% or greater.

Crystalline Form A may have an exothermic peak which has a startingpoint at about 219° C. and its highest point at about 225° C. in adifferential scanning calorimetry (DSC, 10° C./min). Crystalline Form Amay have an exothermic peak at about 222±4° C. in a DSC (10° C./min).

Crystalline Form A may have, in a thermogravimetric analysis (TGA), aweight loss of 4% or less at the temperature of up to 100° C., and maydecompose at or above 200° C.

In another aspect of the present invention, Crystalline Form A of thecompound of Formula 1 may be in a substantially pure form.

The term “substantially pure” as used herein means at least 95% purity,preferably 97% purity, or more preferably 99% purity, wherein 95% puritymeans no more than 5%, 97% purity means no more than 3%, and 99% puritymeans no more than 1%, of any other form of the compound of Formula 1(other crystalline form, amorphous form, and so forth) being present.

In one embodiment, Crystalline Form A of the compound of Formula 1 mayhave 95% or greater purity in crystalline form.

Crystalline Form A of the compound of Formula 1 was found to havesignificantly improved storage stability and purity (see ExperimentalExample 1). According to long-term stability purity test of ExperimentalExample 1, about 0.20 wt % of total impurities were found in CrystallineForm A after 24 months at 25±2° C. Therefore, Crystalline Form A of thecompound of Formula 1 enables preparation of medicines having improvedstability.

Furthermore, Crystalline Form A of the compound of Formula 1 may beprepared to have a higher safety profile. Dichloromethane was used as asolvent in the previous method of preparing the compound of Formula 1.Dichloromethane is very toxic and is classified as a Class 2 solvent,i.e., a solvent that is regulated in medicines at residual amounts of600 ppm or less according to the International Council for Harmonization(ICH) guideline Q3C [Guideline on Impurities for Residual Solvents].However, it is difficult to lower the amount of residual solvents, asexpensive treatment processes are required. Therefore, Crystalline FormA of the compound of Formula 1 has the advantage of being safer and moreeconomical in terms of production for use as a medicinal drug substance.

Method of Preparing Crystalline Form A of the Compound of Formula 1

Another aspect of the present invention provides a method of preparingCrystalline Form A of the compound of Formula 1.

In one embodiment, the method comprises steps of:

dissolving4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onein one or more solvents selected from a group consisting of a C₁-C₃alcohol, acetone, ethyl acetate, and methyl t-butyl ether; and

adding a hydrochloric acid solution.

In another embodiment, the method comprises steps of:

dissolving4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onein one or more solvents selected from a group consisting of a C₁-C₃alcohol, acetone, ethyl acetate, and methyl t-butyl ether to obtain amixture;

cooling the mixture;

adding a hydrochloric acid solution;

raising the temperature to about room temperature, cooling, and stirringto obtain a solid; and

filtering, washing, and drying the solid.

In another embodiment, the method comprises steps of:

(a) dissolving4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onein one or more solvents selected from a group consisting of a C₁-C₃alcohol, acetone, ethyl acetate, and methyl t-butyl ether to obtain amixture;

(b) cooling the obtained mixture to about 0° C.;

(c) adding, to the mixture, a hydrochloric acid solution, optionally,together with a mixture of a hydrochloric acid solution and one or moresolvents selected from a group consisting of a C₁-C₃ alcohol, acetone,ethyl acetate, and methyl t-butyl ether;

(d) raising the temperature to about room temperature;

(e) stirring the mixture for about 10 to about 14 hours;

(f) cooling the mixture to about 10 to about 20° C.;

(g) stirring the cooled mixture for about 20 to about 60 minutes toobtain a solid; and

(h) filtering, washing, and drying the solid.

In step (a),4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,i.e., the compound of Formula 2, may be dissolved in one or moresolvents selected from a group consisting of a C₁-C₃ alcohol, acetone,ethyl acetate, and methyl t-butyl ether, and subsequently cooled down toabout 0° C. accordingly to step (b), and thereafter step (c) may beperformed. The solvent may be, for example, a single solvent, such asmethanol, ethanol, isopropyl alcohol, acetone, ethyl acetate, and methylt-butyl ether, or a mixed solvent thereof, e.g., a mixed solvent ofmethanol and methyl t-butyl ether.

The free base form of the compound of Formula 1, that is,4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,may be prepared according to the methods disclosed in US '973, thedisclosure of which is incorporated herein in its entirety by reference.However, the embodiments described herein are not limited thereto, andthe free base form of the compound of Formula 1 may be prepared usingany method known to the person of ordinary skill in the relevant art.

In the present preparation method, specifically, in step (c), thehydrochloric acid solution may be added as a solution in a solvent ofwater, alkyl acetate (e.g., ethyl acetate, etc.), alkyl ether (e.g.,diethyl ether, etc.), or alkyl alcohol (e.g., isopropyl alcohol, ethylalcohol, etc.). In one specific embodiment, the solvent may be water,ethyl acetate, diethyl ether, isopropyl alcohol, or ethyl alcohol. Morespecifically, the hydrochloric acid solution may be about 30 to 40%,e.g., 37.0% aqueous solution, 1.0 M solution in ethyl acetate, 1.0 Msolution in diethyl ether, 5 to 6 N solution in isopropyl alcohol, or1.25 M solution in ethyl alcohol.

The amount of the hydrochloric acid in the hydrochloric acid solution orthe mixed solution of the hydrochloric acid solution and the solvent maybe about 1.0 to about 2.0 equivalents with respect to 1 equivalent ofthe free base form of the compound of Formula 1. The volume of thehydrochloric acid solution or the mixed solution may be in a ratio (v/w)of about 0.1:1 to about 20:1 with respect to the weight of the free baseform of the compound of Formula 1. The solvent in step (c) may be one ormore selected from a group consisting of a C₁-C₃ alcohol, acetone, ethylacetate, and methyl t-butyl ether.

In step (f), the cooling temperature may be from about 10° C. to about20° C., and preferably from about 12° C. to about 17° C., and morepreferably about 15° C. When stirred, after the cooling, for about 20minutes to about 60 minutes, and more preferably about 30 to 40 minutesin step (g), Crystalline Form A in a solid phase may be obtained.Thereafter, filtering, washing, and drying may be performed in step (h).

The washing and drying steps are not specifically limited. The washingmay be performed using the solvent used in step (a). The drying may beperformed using any method which does not affect the stability of thecrystalline form of the compound of Formula 1, for example, at atemperature of about 40° C. to about 50° C. for about 15 hours to 30hours.

In the case where solvents other than those described above are used forcrystallization, another crystalline form may be obtained. For example,when dichloromethane or a mixture of dichloromethane and methanol isused as a solvent, Crystalline Form C of Formula 1 is obtained.Crystalline Form C may exhibit an XRPD pattern comprising peaks atdiffraction angles (2θ)±0.2° of 3.5°, 7.1°, 12.9°, 21.6°, 24.4°, and25.3°. The XRPD pattern of Crystalline Form C is shown in FIG. 5.

In another example, an amorphous form is obtained by a processcomprising steps: completely dissolving a compound of Formula 1 in HClsalt in an excess amount of methanol, concentrating the solvent, rapidlyadding acetone to the residual to obtain a crystal, followed byconcentrating the solvent, dispersing and stirring the residual solid inn-Heptane, and filtering. The XRPD pattern of the amorphous form isshown in FIG. 8.

Medical Usage and Pharmaceutical Composition

Another aspect of the present invention provides a pharmaceuticalcomposition comprising Crystalline Form A of the compound of Formula 1as an active ingredient and at least one pharmaceutically acceptablecarrier or excipient.

The pharmaceutical composition may comprise about 80% or greater,preferably about 90% or greater, more preferably about 95% or greater,and most preferably about 99% or greater of Crystalline Form A of thecompound of Formula 1 with respect to a total amount of the compound ofFormula 1. The remainder may be in any other form of the compound ofFormula 1 (other possible crystalline forms, amorphous form, and soforth).

As disclosed in US '973, the compound of Formula 1 was found to exhibitPARP inhibitory activity and have anticancer activity, and therefore canbe used in the treatment of cancer caused, specifically, by defectiveDNA-damage repair, or a genetic defect in the BRCA1, BRCA2, or ERGfusion genes. As used herein, the term “genetic defect” may include, butis not limited to, a genetic mutation or lack (deficiency) of a gene, ora defect in gene expression.

The pharmaceutical composition may be used for the treatment of cancer.

The cancer may be caused by defective DNA-damage repair, or a geneticdefect in the BRCA1, BRCA2, or ERG fusion gene. For example, the cancermay be selected from the group consisting of breast cancer, ovariancancer, pancreatic cancer, gastric cancer, lung cancer, colon cancer,brain tumor, prostate cancer, and Ewing's sarcoma. Specifically, thecancer may be breast cancer or ovarian cancer.

When administered to a human patient, a total daily dosage ofCrystalline Form A may vary depending on the administration route,administration time, types of other compounds used in combination, orthe patient's age, sex, weight, status, medical history, and so forth.Therefore, the dosage of the compound may be determined within the rangein which a desired therapeutic effect is achieved without causingharmful or serious adverse effects.

The pharmaceutical composition may be in oral or parenteral dosage form.

For oral dosage forms, the carrier used may include sweetening agents,binders, resolvents, solublizing agents, wetting agents, emulsifyingagents, isotonic agents, adsorbents, disintegrating agents,antioxidants, antiseptics, lubricants, fillers, flavoring agents,coating agents, and so forth. For example, the carrier may includelactose, calcium hydrogen phosphate, hydroxypropyl cellulose,carboxymethyl cellulose, colloidal silicon dioxide, fumed silica,magnesium stearate, talc, agar, water, ethanol, polyethylene glycol,polyvinylpyrrolidone, sodium chloride, calcium chloride, orange essence,strawberry essence, vanilla flavor, Opadray white, and so forth.

Examples of available injectable carriers include distilled water,saline, glucose solutions, pseudo-glucose solutions, alcohols, glycolethers (for example, polyethylene glycol 400), oils, fatty acids, fattyacid esters, glycerides, surfactants, suspending agents, emulsifyingagents, and so forth.

Another aspect provides a method for preventing or treating a cancer,comprising administering, to an individual or patient in need of cancerprevention or treatment, a pharmaceutically effective amount ofCrystalline Form A of the compound of Formula 1.

The above descriptions of the pharmaceutical composition according to anaspect of the present invention may be applied per se to details of themethod for preventing or treating a cancer.

The dose used in the method for preventing or treating a cancer may bean amount effective for the prevention or treatment. The abovedescription of the dose of the pharmaceutical composition may apply perse to the method for preventing or treating a cancer.

The description regarding medical usage and pharmaceutical compositionsof the compound of Formula 1 disclosed in US '973 may apply to those ofCrystalline Form A of the compound of Formula 1 according to the presentinvention.

Hereinafter, the present invention will be described in more detail withreference to the following Examples. However, these Examples are forillustrative purposes only, and the invention is not intended to belimited by these Examples.

Analysis Apparatus and Method of Measurement

1. X-ray Powder Diffraction (XRPD)

X-ray powder diffraction (XRPD) analyses of samples were performed inthe range from 3° 2θ to 50° 2θ using a D8 Advance (Bruker ASX, Germany)analyzer. The measurement was performed as follows:

Anode material (Kα): Cu-Kα (1.54056 Å)

Scan range: 3° to 50°

Generator settings: 40 mA, 40.0 kV

Scan speed: 0.5 sec/step

Temperature: 20° C.

Step size: 0.02° 2θ

Rotation: no use

2. Differential Scanning Calorimetry (DSC)

Differential scanning calorimetry (DSC) analysis was performed using anAUTO MDSC Q20/RSC40 (TA Instruments) in the temperature range from 25°C. to 300° C. at a heating rate of 5° C./min or 10° C./min. A sample inan amount of 5 mg to 10 mg was weighed and added into an aluminum DSCfan, and the fan was sealed with a perforated aluminum lid in anon-sealing manner. Then, the sample was heated at a scan speed of 5°C./min or 10° C./min from 25° C. to 300° C., and the heat flow reactiongenerated was monitored in a DSC.

3. Thermal Gravimetric Analysis (TGA)

Thermal gravimetric analysis (TGA) was performed using a TGA Q50 (TAInstruments) in the temperature range from 25° C. to 300° C. at aheating rate of 10° C./min.

4. Gas Chromatography (GC)

Gas Chromatography (GC) was performed using a Agilent 7697A HeadspaceSampler/7890A GC Chemstation.

5. Karl Fischer (KF) Analysis

Karl Fischer (KF) analysis was performed using (i) Metrohm 795 KFTTitrino System, 795 Key Pad, 703 Ti Stand, and (ii) Mettler Toledo V20SCompact Volumetric KF Titrator.

Preparation Example: Preparation of a Compound of Formula 2

A compound of Formula 2,4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,was prepared according to the process including Steps 1 to 5 asdescribed below.

Step 1. Preparation of tert-butyl3-[(cyclopropylamino)methyl]azetidine-1-carboxylate

1.0 kg of tert-butyl 3-formylazetidine-1-carboxylate was added into areactor, and 6.5 kg of trifluoroethanol was added thereto. 0.3 kg ofcyclopropylamine was added at 0° C., stirring at ambient temperature for1 hour, followed by cooling the reactor down to 0° C. 0.2 kg of sodiumborohydride was slowly added and stirred at ambient temperature for 1hour, and then the reactor was cooled down to 0° C. After 10.0 kg ofwater was slowly added thereto, the reaction mixture was extracted with6.7 kg of dichloromethane, and the thus-obtained aqueous layer wasfurther extracted with 6.7 kg of dichloromethane. The organic layer waswashed with a 15% sodium chloride aqueous solution, treated with 0.5 kgof anhydrous magnesium sulfate, filtered and then concentrated underreduced pressure, to thereby yield 0.98 kg of the titled compound as ayellow oil (Yield: 80.1%). The titled compound was used in a subsequentprocess without a separate purification process.

¹H NMR (CDCl₃, 400 MHz) δ 3.99 (t, 2H), 3.60-3.57 (m, 2H), 2.90 (d, 2H),2.66-2.62 (m, 1H), 2.11-2.06 (m, 1H), 1.59 (br, 1H), 1.44 (s, 9H),0.46-0.42 (m, 2H), 0.32-0.28 (m, 2H)

Step 2. Preparation of tert-butyl3-([([(9H-fluorene-9-yl)methoxy]carbonyl)(cyclopropyl)amino]methyl)azetidine-1-carboxylate

4.0 kg of dichloromethane was added into a reactor, 300.0 g oftert-butyl 3-[(cyclopropylamino)methyl]azetidine-1-carboxylate preparedin Step 1 and 188.4 g of diisopropylethylamine were sequentially addedthereto, and then the reactor was cooled down to 0° C. 377.2 g of9-fluorenylmethoxycarbonyl chloride was slowly added into the reactorsuch that the internal temperature of the reactor did not exceed 20° C.,and the reaction mixture was stirred for 1 hour. 5.0 kg of water wasadded thereto to wash the organic layer, and the organic layer wasfurther washed with 5.0 kg of a 1 N hydrochloric acid aqueous solution.The organic layer was further washed with a 15% sodium chloride aqueoussolution and treated with 250.0 g of anhydrous magnesium sulfate,filtered, and concentrated under reduced pressure, to therebyquantitatively yield 576.7 g of the titled compound as a yellow oil. Thetitled compound was used in a subsequent process without a separatepurification process.

¹H NMR (CDCl₃, 400 MHz) δ 7.72 (d, 2H), 7.56 (d, 2H), 7.36 (t, 2H),7.30-7.26 (m, 2H), 4.52 (d, 2H), 4.17 (t, 1H), 3.89-3.85 (m, 2H), 3.56(m, 2H), 3.30 (m, 2H), 2.60 (m, 1H), 2.28 (m, 1H), 1.43 (s, 9H), 0.61(m, 2H), 0.45 (m, 2H)

Step 3. Preparation of(9H-fluorene-9-yl)methyl(azetidine-3-ylmethyl)(cyclopropyl)carbamatehydrochloride

1.0 L of ethanol was added into a reactor, 100.0 g of tert-butyl3-([([(9H-fluorene-9-yl)methoxy]carbonyl)(cyclopropyl)amino]methyl)azetidine-1-carboxylateprepared in Step 2 and 24.8 mL of concentrated hydrochloric acid weresequentially added thereto, and then the resultant mixture was heated.The reaction proceeded at reflux temperature for 30 minutes, and thenthe reaction mixture was concentrated under reduced pressure. 170 mL ofethyl acetate and 430 mL of n-hexane were added to the residue, stirredat ambient temperature overnight, filtered, and then dried at 40° C., tothereby yield 78.2 g of the titled compound (Yield: 91.2%).

¹H NMR (CDCl₃, 400 MHz) δ 9.63 (br, 1H), 9.40 (br, 1H), 7.75-7.70 (m,2H), 7.60-7.55 (m, 2H), 7.38 (t, 2H), 7.32-7.29 (m, 2H), 4.52 (d, 2H),4.18 (t, 1H), 3.99 (m, 2H), 3.81 (m, 2H), 3.44-3.28 (m, 2H), 2.94 (m,1H), 2.27 (m, 1H), 0.60-0.59 (m, 2H), 0.43 (m, 2H)

Step 4. Preparation of(9H-fluorene-9-yl)methylcyclopropyl([1-(2-fluoro-5-[(4-oxo-3,4-dihydrophthalazin-1-yl)methyl]benzoyl)azetidine-3-yl]methyl)carbamate

300 mL of dichloromethane was added into a reactor, and 29.8 g of2-fluoro-5-[(4-oxo-3,4-dihydrophthalazin-1-yl)methyl]benzoic acid and17.9 g of 1,1′-carbonyldiimidazole were sequentially added thereto. Thereaction proceeded at ambient temperature for 1 hour, and then thereactor was cooled down to 15° C. Then, 42.3 g of(9H-fluorene-9-yl)methyl(azetidine-3-ylmethyl) (cyclopropyl)carbamatehydrochloride prepared in Step 3 was added thereto, and 19.4 g ofdiisopropylamine was slowly added thereto. The reaction mixture wasstirred at ambient temperature for 1 hour, 300 mL of water was addedthereto to wash the organic layer, and then the organic layer wasfurther washed with a 1 N hydrochloric acid aqueous solution and a 1 Nsodium carbonate aqueous solution. The organic layer was further washedwith a 5% sodium chloride aqueous solution, treated with 10.0 g ofanhydrous magnesium sulfate, filtered, and then concentrated underreduced pressure. 70 mL of ethyl acetate and 350 mL of n-hexane wereadded to the residue, stirred at ambient temperature overnight,filtered, and then dried at 50° C., to thereby yield 63.2 g of thetitled compound (Yield: 91.3%).

¹H NMR (DMSO-d₆, 400 MHz) δ 12.60 (s, 1H), 8.26-8.24 (m, 1H), 7.97 (d,1H), 7.90-7.78 (m, 4H), 7.65-7.62 (m, 2H), 7.48-7.28 (m, 7H), 4.51-4.48(m, 2H), 4.32 (s, 2H), 4.26-4.23 (m, 1H), 3.97-3.86 (m, 2H), 3.62-3.56(m, 2H), 3.30-3.25 (m, 2H), 2.24 (m, 1H), 1.24-1.23 (m, 1H), 0.48 (m,2H), 0.38-0.35 (m, 2H)

Step 5. Preparation of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one

150 mL of acetonitrile was added into a reactor, and 30.0 g of(9H-fluorene-9-yl)methylcyclopropyl([1-(2-fluoro-5-[(4-oxo-3,4-dihydrophthalazin-1-yl)methyl]benzoyl)azetidine-3-yl]methyl)carbamateprepared in Step 4 and 34.5 g of piperidine were sequentially addedthereto and stirred at ambient temperature for 1 hour. After thereaction mixture was concentrated under reduced pressure, 300 mL of a 2N hydrochloric acid aqueous solution was added to the residue, stirredfor 1 hour, and then filtered through diatomaceous earth. Then, thefiltrate was adjusted to pH 9 or greater with a 1 N sodium hydroxidesolution and extracted by adding 300 mL of dichloromethane. The aqueouslayer was further extracted by adding 300 mL of dichloromethane thereto,and then the organic layer was mixed therewith, washed with a 5% sodiumchloride aqueous solution, and then concentrated. 80 mL of methanol and40 mL of dichloromethane were added to the residue, and then 150 mL ofacetone was slowly added thereto. The resulting solid was stirred atambient temperature overnight, filtered, and dried at 40° C. to yield17.5 g the titled compound (Yield: 90.1%).

¹H NMR (DMSO-d₆, 400 MHz) δ 12.62 (s, 1H), 8.27-8.25 (m, 1H), 7.97 (d,1H), 7.90-7.86 (m, 1H), 7.84-7.79 (m, 1H), 7.46-7.43 (m, 2H), 7.22-7.18(m, 1H), 4.32 (s, 2H), 4.04-3.56 (m, 4H), 2.73-2.63 (m, 3H), 2.30 (br,1H), 2.00-1.95 (m, 1H), 0.33-0.12 (m, 4H)

Preparation of Crystalline Form A of Compound of Formula 1 Example 1:Preparation of Crystalline Form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

10.0 mL of methyl alcohol was added to 1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and mixed and cooled down to 0° C. Subsequently, after 0.2 ml of a 37.0%aqueous hydrochloric acid solution was added thereto, the temperaturewas raised to room temperature, and the mixture was stirred for 12hours. After cooling to 15° C., the mixture was additionally stirred for30 minutes. The obtained solid was then filtered, washed with methylalcohol, and dried to obtain 0.76 g of Crystalline Form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride (Yield: 69.7%, DSC maximum peak temperature at a heatingrate of 10° C./min: 222.81° C.).

The results of XRPD, DSC, and TGA of the obtained Crystalline Form A areshown in FIGS. 1, 2, and 3, respectively.

The locations of peaks of Crystalline Form A and the relativeintensities thereof are represented in the following table.

TABLE 1 Peak location (2θ) Relative intensity (I/I_(O) %) 9.1° 38.411.9° 18.2 13.2° 32.6 13.7° 64.4 15.9° 65.6 16.8° 40.0 18.1° 37.4 23.2°40.6 24.1° 100.0 25.5° 30.1 26.6° 48.9

Example 2: Preparation of Crystalline Form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

20.0 mL of acetone was added to 1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 0.2mL of a 37.0% aqueous hydrochloric acid solution was added thereto, thetemperature was raised to room temperature, and the resultant mixturewas stirred for 12 hours. After cooling to 15° C., the mixture wasadditionally stirred for 30 minutes. The solid thus obtained wasfiltered, washed with acetone, and then dried to thereby obtain 0.89 gof4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride Crystalline Form A. (Yield: 81.7%, DSC maximum peaktemperature at a heating rate of 10° C./min: 223.26° C.).

The results of XRPD of the obtained Crystalline Form A are shown in FIG.4.

Example 3: Preparation of Crystalline Form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

10.0 mL of ethyl alcohol was added to 1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 0.2mL of a 37.0% aqueous hydrochloric acid solution and 5.0 mL of ethylalcohol were mixed together and then added to the reaction solution, thetemperature was raised to room temperature, and the resultant mixturewas stirred for 12 hours. After cooling to 15° C., the mixture wasadditionally mixed for 30 minutes. The solid thus obtained was filtered,washed with ethyl alcohol, and then dried to thereby obtain 0.57 g ofCrystalline Form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride. (Yield: 52.3%, DSC maximum peak temperature: 219.26° C.).

The results of XRPD of the obtained Crystalline Form A are shown in FIG.4.

Example 4: Preparation of Crystalline Form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

15.0 mL of ethyl acetate was added to 1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 0.2mL of a 37.0% aqueous hydrochloric acid solution and 5.0 mL of ethylacetate were mixed together and then added to the reaction solution, thetemperature was raised to room temperature, and the mixture was stirredfor 12 hours. After cooling down to 15° C., the mixture was additionallystirred for 30 minutes. After the thus obtained solid was filtered,washed with ethyl acetate, and then dried to thereby obtain 0.93 g ofCrystalline Form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride (Yield: 85.3%, DSC maximum peak temperature at a heatingrate of 10° C./min: 222.08° C.).

The results of XRPD of the obtained Crystalline Form A are shown in FIG.4.

Example 5: Preparation of Crystalline Form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

15.0 mL of isopropyl alcohol was added to 1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 0.2mL of a 37.0% aqueous hydrochloric acid solution and 5.0 mL of isopropylalcohol were mixed together and then added to the reaction solution, thetemperature was raised to room temperature, and the mixture was stirredfor 12 hours. After cooling down to 15° C., the mixture was additionallymixed for 30 minutes. The solid thus obtained was filtered, then washedwith isopropyl alcohol, and then dried to thereby obtain 0.96 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride Crystalline Form A (Yield: 88.1%, DSC maximum peaktemperature at a heating rate of 10° C./min: 223.81° C.).

The results of XRPD of the obtained Crystalline Form A are shown in FIG.4.

Example 6: Preparation of Crystalline Form A of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

10.0 mL of methyl alcohol was added to 1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 0.2mL of a 37.0% aqueous hydrochloric acid solution was added to thereaction solution, and then 15.0 mL of methyl tert-butyl ether was addedthereto, the temperature was raised to room temperature, and the mixturewas stirred for 12 hours. After cooling to 15° C., the mixture wasadditionally stirred for 30 minutes. The solid thus obtained wasfiltered, then washed with acetone, and then dried to thereby obtain0.95 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride Crystalline Form A (Yield: 87.2%, DSC maximum peaktemperature at a heating rate of 10° C./min: 225.02° C.).

The results of XRPD of the obtained Crystalline Form A are shown in FIG.4.

Preparation of Crystalline Form C of Compound of Formula 1 Example 7:Preparation of Crystalline Form C of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

10.0 mL of dichloromethane was added to 1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 0.2mL of a 37.0% aqueous hydrochloric acid solution was thereto, thetemperature was raised to room temperature, followed by stirring for 12hours. After cooling to 15° C., the mixture was additionally stirred for30 minutes. The solid thus obtained was filtered, washed with acetone,and then dried to obtain 1.07 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride Crystalline Form C (Yield: 98.1%, DSC maximum peaktemperature at a heating rate of 5° C./min: 214.60° C.).

The XRPD, DSC, and TGA graphs of Crystalline Form C of Example 7 areshown in FIGS. 5, 6, and 7, respectively. The locations ofcharacteristic peaks of Crystalline Form C and the relative intensitiesthereof are represented in Table 2 below.

TABLE 2 Peak location (2θ) Relative intensity (I/I_(O) %) 3.5 100.0 7.128.1 12.9 47.9 21.6 45.3 24.4 69.3 25.3 70.9

Example 8: Preparation of Crystalline Form C of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

12.0 mL of methyl alcohol and 6.0 mL of dichloromethane were added to1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 2.5mL of 1.0 M hydrochloric acid solution in ethyl acetate was added to thereaction solution, the temperature was raised to room temperature,followed by stirring for 5 hours. After cooling to 15° C., the mixturewas additionally stirred for 30 minutes. The solid thus obtained wasfiltered, washed with methyl alcohol, and then dried to obtain 0.70 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride Crystalline Form C (Yield: 64.2%, DSC maximum peaktemperature at a heating rate of 10° C./min: 223.34° C.).

Example 9: Preparation of Crystalline Form C of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

12.0 mL of methyl alcohol and 6.0 mL of dichloromethane were added to1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 2.5mL of 1.0 M hydrochloric acid solution in diethyl ether was added to thereaction solution, the temperature was raised to room temperature,followed by stirring for 5 hours. After cooling to 15° C., the mixturewas additionally stirred for 30 minutes. The solid thus obtained wasfiltered, washed with methyl alcohol, and then dried to obtain 0.68 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride Crystalline Form C (Yield: 62.4%, DSC maximum peaktemperature at a heating rate of 10° C./min: 222.36° C.).

Example 10: Preparation of Crystalline Form C of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

12.0 mL of methyl alcohol and 6.0 mL of dichloromethane were added to1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 0.5mL of 5 to 6 N hydrochloric acid solution in isopropyl alcohol was addedto the reaction solution, the temperature was raised to roomtemperature, followed by stirring for 5 hours. After cooling to 15° C.,the mixture was additionally stirred for 30 minutes. The solid thusobtained was filtered, washed with acetone, and then dried to obtain0.65 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride Crystalline Form C (Yield: 59.6%, DSC maximum peaktemperature at a heating rate of 10° C./min: 222.45° C.).

Example 11: Preparation of Crystalline Form C of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

12.0 mL of methyl alcohol and 6.0 mL of dichloromethane were added to1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-one,and then mixed together and cooled down to 0° C. Subsequently, after 2.0mL of 1.25 M hydrochloric acid solution in ethyl alcohol was added tothe reaction solution, the temperature was raised to room temperature,followed by stirring for 5 hours. After cooling to 15° C., the mixturewas additionally stirred for 30 minutes. The solid thus obtained wasfiltered, washed with acetone, and then dried to obtain 0.43 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride Crystalline Form C (Yield: 39.5%, DSC maximum peaktemperature at a heating rate of 10° C./min: 221.16° C.).

It was confirmed from Examples 7-11 that Crystalline Form C was obtainedwhen using dichloromethane alone or the mixture solvent ofdichloromethane and methanol, in any type of hydrochloric acid.

Preparation of Amorphous Form of Compound of Formula 1 Examples 12:Preparation of Amorphous Form of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride

90.0 mL of methyl alcohol was added to 1.0 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride, and then mixed together and concentrated. 20.0 mL ofacetone was rapidly added into the concentrated residual to result in acrystal, followed by concentrating. 15.0 mL of n-heptane was added intothe concentrated residual, stirred for 5 minutes, and filtered to obtain0.75 g of4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onehydrochloride Amorphous Form (Yield: 75.0%).

The results of XRPD of the obtained amorphous form are shown in FIG. 8.

The obtained amorphous form readily absorbed water during the storage,i.e., it was hygroscopic, whereby the color turned yellow. It was thusconfirmed that the amorphous form was not suitable for use as amedicinal drug substance.

Experimental Example 1: Stability Test of Crystalline Form A

Crystalline Form A of the compound of Formula 1 prepared in Example 1was stored under long-term storage conditions (25±2° C., and Relativehumidity: 60±5%). Samples were taken after 3 months, 6 months, 9 months,12 months, 18 months, and even 24 months from the onset of the storageto measure total impurities content by high performance liquidchromatography (HPLC). The results are shown in Table 3.

TABLE 3 Results of long-term stability purity test of Crystalline Form AStorage period 3 6 9 12 18 24 Initial months months months months monthsmonths Total impurities 0.14% 0.15% 0.16% 0.15% 0.14% 0.19% 0.20%content (wt %)

As such, the above results indicate that Crystalline Form A of thecompound of Formula 1 exhibits high stability under long-term storageconditions. Thus, Crystalline Form A is desirable for use as a medicinaldrug substance.

Those of ordinary skill in the art will recognize that the presentinvention may be embodied in other specific forms without departing fromits spirit or essential characteristics. The described embodiments areto be considered in all respects only as illustrative and notrestrictive. The scope of the present invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within the scope of the present invention.

The invention claimed is:
 1. A crystalline form of a compound of Formula1, exhibiting an X-ray powder diffraction (XRPD) pattern comprisingpeaks at 2θ±0.2° values of 13.7°, 15.9°, and 24.1°:


2. The crystalline form of claim 1, wherein the XRPD pattern comprisespeaks at three or more 2θ±0.2° values selected from the group consistingof 9.1°, 11.9°, 13.2°, 13.7°, 15.9°, 16.8°, 18.1°, 23.2°, 24.1°, 25.5°,and 26.6°.
 3. The crystalline form of claim 1, wherein the XRPD patterncomprises peaks at 2θ±0.2° values of 9.1°, 13.2°, 13.7°, 15.9°, 16.8°,24.1°, and 26.6°.
 4. The crystalline form of claim 1, wherein the XRPDpattern comprises peaks at 2θ±0.2° values of 9.1°, 11.9°, 13.2°, 13.7°,15.9°, 16.8°, 18.1°, 23.2°, 24.1°, 25.5°, and 26.6°.
 5. The crystallineform of claim 1, wherein each 2θ value of the peaks has the anglevariation ±0.1°.
 6. The crystalline form of claim 1, having a DSCexothermic peak at a temperature of 222±4° C.
 7. The crystalline form ofclaim 1, wherein the crystalline form has, in a thermogravimetricanalysis (TGA), a weight loss of 4% or less up to 100° C., anddecomposes at or above 200° C.
 8. The crystalline form of claim 1,wherein the crystalline form is substantially pure.
 9. The crystallineform of claim 1, wherein the crystalline form is at least 95% pure. 10.A method of preparing the crystalline form according to claim 1, themethod comprising: dissolving4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onein one or more solvents selected from a group consisting of a C₁-C₃alcohol, acetone, ethyl acetate, and methyl t-butyl ether; and adding ahydrochloric acid solution.
 11. A method of preparing a crystalline formaccording to claim 1, the method comprising: dissolving4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onein one or more solvents selected from a group consisting of a C₁-C₃alcohol, acetone, ethyl acetate, and methyl t-butyl ether to obtain amixture; cooling the mixture; adding a hydrochloric acid solution;raising the temperature to about room temperature, cooling, and stirringto obtain a solid; and filtering, washing, and drying the solid.
 12. Amethod of preparing a crystalline form according to claim 1, the methodcomprising: dissolving4-[3-(3-[(cyclopropylamino)methyl]azetidine-1-carbonyl)-4-fluorobenzyl]phthalazin-1(2H)-onein one or more solvents selected from a group consisting of a C₁-C₃alcohol, acetone, ethyl acetate, and methyl t-butyl ether to obtain amixture; cooling the mixture formed to about 0° C.; adding, to themixture, an aqueous hydrochloric acid solution, or a mixture of ahydrochloric acid solution and one or more solvents selected from agroup consisting of a C₁-C₃ alcohol, acetone, ethyl acetate, and methylt-butyl ether; raising the temperature to about room temperature;stirring the mixture for about 10 to about 14 hours; cooling the mixtureto about 10 to about 20° C.; stirring the cooled mixture for about 20 toabout 60 minutes to obtain a solid; and filtering, washing, and dryingthe solid.
 13. A method of preparing a crystalline form according toclaim 10, wherein the hydrochloric acid solution is added as a solutionin water, alkyl acetate, alkyl ether, or alkyl alcohol.
 14. A method ofpreparing a crystalline form according to claim 13, wherein thehydrochloric acid solution is added as a solution in water, ethylacetate, diethyl ether, isopropyl alcohol, or ethyl alcohol.
 15. Amethod of preparing a crystalline form according to claim 10, whereinthe method does not comprise a concentration.